Fibrous product and process of making the same



Jan. 27, 1970 w, lRwlN ETAL FIBROUS PRODUCT AND PROCESS OF MAKING THESAME 2 Sheets-"Sheet 1 Original Filed Dec. 26, 1962 W m Cm MN, Wm MATTORNEYS Jan. 27, 1970 w, mw ETAL 3,491,527

FIBROUS PRODUCT AND PROCESS OF MAKING THE SAME Original Filed Dec. 26,1962 2 Sheets-Sheet 2 FEQE g? Y INVENTORS' Q WINE/EL!) 7. AQW/IVWAR/261V W. DRUMMON BY a A ORNEY;

United States Patent 3,491,527 FIBROUS PRODUCT AND PROCESS OF MAKING THESAME Winfield T. Irwin, Pittsburgh, and Warren W. Drummond, AllisonPark, Pa., assignors to PPG Industries Inc., a corporation ofPennsylvania Continuation of application Ser. No. 246,889, Dec. 26,

1962. This application Feb. 15, 1968, Ser. No. 705,666

Int. Cl. D02g 3/20 U.S. Cl. 57140 16 Claims ABSTRACT OF THE DISCLOSURE Apermanently crimped, multifilament fiber glass prod not produced bycollecting a plurality of longitudinally extending, sized, fiber glassfilaments into a strand, crimping said strand, heating said crimpedstrand at a temperature sufficient to soften the filaments of said,strand and to remove size, cooling said softened filaments to impartpermanent crimp in a plurality of directions and winding.

said strand under tension and in a substantially untwisted state into apackage.

Cross-reference to related applications This application is acontinuation of application Ser. No. 246,889, filed Dec. 26, 1962, nowabandoned, by Winfield T. Irwin and Warren W. Drummond for FibrousProducts and Process of Making The Same.

This invention relates to a fibrous product and the process of makingthe same and more particularly to a fibrous product formed from aplurality of continuous glass fibers and the method of making thefibrous product.

In the manufacture of'a continuous fiber glass strand, a number ofindividual glass filaments or fibers are drawn from an electricallyheated platinum bushing containing a supply of molten glass. Theindividual filaments are grouped into a strand and the strand is woundonto a forming tube. There is no twist in the strand as it is formed andthe filaments are bonded together with a suitable organic binder. Thebinder is applied to each of the individual filaments prior to the timethat they are grouped into a strand and wound on the forming tube. Thestrand is removed from the forming tube and wound on bobbins or othersuitable devices for the making of yarn to be later used in knitting orweaving fabrics.

Preshaped expanded fibrous mats, as distinguished from the abovediscussed strands, may be formed by several different processes. In oneprocess the mechanically drawn filaments are chopped into short segmentsand thereafter, by means of either picking or air blowing, are randomlydeposited on a collecting means. The expanded fibrous mats are thereforeformed of short lengths of randomly grouped filaments and have a highbulk and low density. An organic binder is usually applied to the matsafter they are formed to hold the randomly grouped short filamentstogether. The expanded mats with the organic binder have limitedresiliency.

It is apparent that the apparatus required to make preshaped expandedfibrous mats by the above process does not readily lend itself toforming the fibrous mats at the ultimate point of use. It has,therefore, been the practice to make the expanded fibrous mats atcentralized locations and transport them to the ultimate point of use ina conventional manner. Thus, the transportation of the high bulk, lowdensity fibrous mats accounted for a substantial portion of their cost.Substantial space is required to store the high bulk, low densitypreshaped fibrous mats.

The preshaped fibrous mats made by the known processes have a furtherlimitation in that they do not readily fill irregularly shaped cavities.The mats must be sized, cut and fitted to be properly utilized onirregularly shaped objects and in irregularly cavities.

There is a need for a high bulk and low density fibrous product that canbe used to fill irregularly shaped cavities. Such a product wouldeliminate much of the manual labor now required to install conventionalfibrous mats. There is, moreover, a greater need for a high bulk, lowdensity fibrous product that does not require substantial space duringtransportation and storage.

The fibrous product obtained by the process of the present invention hasa high bulk and a low density. The product is transported to the pointof ultimate use and stored as a compact, high density, low bulk yarn. Byinexpensive, portable apparatus the yarn is expanded at the job siteinto a fibrous product having a high bulk and low density. The fibrousproduct is resilient and has high dimensional stability. The expandedfibrous product may be utilized in much the same manner as fibrous matsin that a continuous strand or tow of high density crimped yarn can beexpanded into a high bulk, low density, continuous expanded tow and theexpanded tow deposited directly into cavitives where preshaped expandedfibrous mats were formerly used. The expanded product may also beutilized as a thermal insulating material which is enclosed in apretailored flexible container that is wrapped around irregularly shapedobjects to form thermal insulating blankets enclosing the irregularlyshaped object. Because of the high dimensional stability of the fibrousproduct, the thermal insulating blankets are readily removable andreusable without settling, sagging or shifting of the fibrous productwithin the flexible container.

Briefly, the process of this invention utilizes a plurality of strandsthat may be manufactured in the manner previously described. The strandsare grouped into a yarn and the yarn is twisted in one direction. Whiletwisted, the yarn is subjected to an elevated temperature. The twistdeforms or crimps the filaments in the strands so that the strands andfilaments have a curved coil springlike configuration and are deformedin three dimensions. The elevated temperature softens the filaments inthe strands so that they are permanently deformed in the curvedconfiguration. The elevated temperature further thermally decomposes theorganic binder that bonds the filaments to each other. The twisted,permanently deformed strands are then untwisted. The diameter of theyarn after crimping and untwisting does not, however, increase to anysubstantial extent. The crimped yarn is a high density, low bulkmaterial that is wound onto a package and transported or stored in thishigh density, low bulk condition.

At the job site the crimped, high density yarn is unwound from thepackage and by means of an air jet is expanded to laterally separate asubstantial number of the filaments in the strands. The yarn as it isexpanded retains its continuity and forms a continuous expanded yarnhaving a low density and a high bulk. The expanded yarn has a generallycylindrical configuration and a majority of the fibers apper to beoriented parallel to the axis of the cylindrical expanded yarn. Theindividual filaments appear to be held together by the mechanicalengagement of the coiled or convoluted portions of the filaments atrandom intervals throughout their length.

Although the fibrous product obtained by the herein described processmay be expanded at the ultimate point of use and utilized as ininsualting material, it is within the scope of this invention to crimpthe yarn and thereafter expand the yarn to a limited extent at the samelocation and utilize the expanded yarn for fabrics or the like. It hasbeen found that the crimped and expanded yarn has desirable texture,springiness and resiliency not present in other yarns made of fibrousstrands.

The term crimped strand or crimped filament as used hereinafter denotesa strand or filament that is permanently deformed and has a generallyhelical configuration similar to that of a coil spring or cork screw.The filaments are deformed in three dimensions, that is, the individualfilaments are deformed into the shape of a helix rather than a flatsinusoidal form where the filaments are deformed in two dimensions. Theterm crimped strand or crimped filament is also intended to denote astrand or filament that is deformed in three dimensions, and when viewedin two dimensions has the appearance of a prolate cycloid, asillustrated in FIGURE 34, page 31 of the Appendix of Mathematical Tablesand Formulas in Langes Handbook of Chemistry, compiled and edited byNorbert Adolph Lange, Ph.D., and published by Handbook Publishers, Inc.,1944-Fifth Edition. It should be understood,*as hereinafter explained,that certain operating conditions may be varied to change the shape ofthe strands and filaments. The term tow as used herein is intended todesignate a collection of strands.

The term stran is intended to designate a collection of filaments.

Accordingly the principal object of this invention is to provide afibrous product formed of continuous filaments and having a low densityand a high bulk.

Another object of this invention is to provide a crimped yarn of fibrousfilaments that has desirable texture, springiness and resiliency.

Another object of this invention is to provide a high bulk, low densityfibrous product of continuous fibrous filaments, the fibrous filamentsbeing so shaped that they mechanically adhere to each other.

A further object of this invention is to provide a process forpermanently crimping fibrous strands and for expanding the permanentlycrimped fibrous strands.

These and other objects and advantages of this invention will be morecompletely described and distinctly pointed out in the followingspecification, the accompanying drawings, and the appended claims.

In describing the preferred embodiment of this invention, illustrated inthe drawings, specific terminology will be resorted to for the sake ofclarity. However, it is not intended to be limited to the specific termsso selected and it is to be understood that each specific term in cludesall technical equivalents which operate in a similar manner toaccomplish a similar purpose.

In the drawings:

FIGURE 1 is a schematic representation of the process for preparingcrimped yarn from continuous strands of fiber glass.

FIGURE 2 is a schematic representation of the process for exapnding thecrimped yarn.

FIGUREB is a sectional view in side elevation of a false twist devicesuitable for use in the process illustrated in FIGURE 1.

FIGURE 4 is a front view of the false twist device illustrated in FIGURE3.

FIGURE 5 is an enlarged view of the air jet employed to expand thecrimped yarn.

FIGURE 6 is an illustration of a segment of high density yarn crimpedaccording to the process of FIG- URE 1.

FIGURE 7 is an illustration of the same segment of crimped yarn after ithas been expanded by the process illustrated in FIGURE 2. The expandedyarn illustrated in FIGURE 7 has a low density.

Referring to FIGURE 1, there is a creel structure 10 on which there arepositioned a plurality of packages 12. Each of the packages 12 has astrand of fiber glass wound thereon. The fiber glass strands'are formedof a plurality of fibrous filaments as previously described. Thefilaments are grouped into a strand and are bonded by means of asuitable binder. The strands 1.4 are threaded through suitable guides 16on the creel structure 10 and are grouped on another guide 18 to form atow 20. Other suitable conventional means can "be utilized in piace ofthe creel structure to form the tow 20.

The tow 20' passes through a tensioning device 22 and then over a roller24. The roiier 24 is carried by a spring 26 which serves as a shockabsorber for abrupt tension changes. The tensioning device 22 can varythe tension of the tow 20 by any suitable means such as an electromagnetic control or the like. A capstan or Godet wheel 28 is positionedadjacent one end of a tubular furnace 30 and twister device 32 ispositioned adjacent the other end of furnace 30. The Godet wheel 28 hasa wedge shaped circumferential recessed portion that exerts a radialgripping action on the tow 20 and serves to stop the tow from twistingaxially, as later explained. The tow 20 extends beneath the Godet wheel28 and through the tubular furnace 30. From the tubular furnace 30- thetow 20 passes through a false twister generally designated by thenumeral 32. The tow 20 extends around roller 34 and around the motordriven pulling roll 36. Both roller 34 and pulling roll 36 may be Godetwheels or they may be fabricated of rubber or the like, The motor drivenpulling roll 36 serves to puil the strands 14 from the packages 12 andthrough the furnace 30 and twister 32. A suitable means is provided withthe pulling roll 36 to vary the linear velocity of the tow 20 as itpasses through the furnace 30 and the twister 32. The end of the tow 20is wound on a winding device or package 38 by means of a surface driventakeup roll 40. A traversing device 42 serves to dstribute the tow Ziion the package 38.

A suitable false twister 32 is illustrated in FIGURES 3 and 4 and has afixed body portion 44 with an axial bore 46. Mounted Within the 'bore 46are a pair of bearings 48 and 50. A tubular spindle 52 is supported inbearings 48 and 50 and is arranged for high speed rotation relative tothe fixed twister body portion 44. Suitable dust seals 54 and 56 aremounted on the spindle 52 and reduce the dust contamination of bearings48 and 50. The spindle 52 has an outwardly flared end portion 58 with aninner recessed portion 66. A disc shaped insert 62 (FIGURE 4) ispositioned in the recessed portion 60 and is suitably secured therein.The insert 62 has four radial slots 64 therein, one of the slotsarranged to have the tow 20 threaded therethrough. The slots 64 areradially spaced in the insert 62 a symmetrical manenr so that the insertand the spindle are symmetrically balanced. The periphery of a frictionwheel =56 abuts the outer wall of spindle 52. The friction wheel 66 isconnected to a var iable speed motor 68 (FIGURE 1) and is arranged torotate the spindle at a high rate of speed. The apparatus schematicaliyillustrated in FIGURE 1 is utilized to permanently crimp or deform thegenerally rectilinear fibers in strands 1 4, as will be later discussed.

In FIGURE 2 the apparatus for expanding the crimped tow is illustrated.The package of crimped tow 38 formed by the process of FIGURE 1 ispositioned on a horizontal spindle 70. The spindle 76 is mounted on anysuitable support, schematically illustrated at 72 in FIGURE 2. Thesupport for the spindle 70 is preferably portable so that the expansionof the crimped tow 20 can be accomplished at any desired location. Thecrimped tow 20 is threaded through an air jet or nozzle generallydesignated by the numeral 74. A source of air enters jet 74 throughconduit 76. Suitable valve means 78 is provided in conduit 76 toregulate the amount of air entering the jet 74. Although a spindle 70'is described as supporting the package of crimped tow, it should beunderstood that other suitable package supports could be utilized tounwind the cri'rnped tow from the package. For example, instead ofrotating the package 38, the crimped tow can be delivered to the jet 7-4over end from a stationary package supported in a suitable manner.

The jet 74 is illustrated in section in FIGURE 5 and has a cylindricalbody portion 80' with an end wall 82.

The end wall 82 has a central inwardly flared aperture 84 terminating inan axial nozzle 86. A disc shaped member 88 is threadably secured to thebody portion 80 and has an axial aperture 90 therethrough with aninwardly fiared portion 92. The member 88 is spaced from the bodyportion end wall 82 and has a threaded connection 94 for air conduit 76.The spaced relation between wall 82 and member 88 provides a cavity 96to distribute the air entering through conduit 76 and is utilized tocontrol the expanded diameter of the tow. Air entering through conduit76 passes through the cavity 96, as indicated by the arrows in FIGURE 5,and an annular jet or stream of air impinges on the cylindrical outersurface of crimped tow to expand the tow 20, as indicated in FIGURE 5.For example, the tow 20 entering the jet 74 has a configuration similarto that illustrated inFIG- URE 6. The expanded tow 20 being ejected fromthe jet 74 has a configuration similar to that illustrated in FIG- URE7. The linear velocity of the tow passing through jet 74 and theexpanded diameter of the tow 20- is controlled by the air pressure andthe spacing between disc 88 and the wall 82.

Operation The process illustrated in FIGURE 1 permanently deforms orcrimps the fibers in strands 14 in the following manner. The strands 14have a generally rectilinear configuration and the filaments of eachstrand are bonded together by a suitable organic binder. The strands aregrouped into the tow 20 having a generally rectilinear configuration atguide 18. The tow is pulled through tensioning device .22, over idler 24and around the Godet Wheel 28. The tow 20 is pulled through furnace andtwitser 32 and around idler 34 and pulling roll 36. The false twister 32imparts a twist to the tow in one direction between false twister 32.and the Godet wheel 28. A twist in the opposite direction is imparted tothe tow 20 from the false twister 32 to the idler 34. The Godet wheel 28and the idler 34 stop the twisting action imparted by the false twister32. The twist imparted between false twister 32 and Godet wheel 28 issubstantially removed from the tow by the opposite twist exerted betweenfalse twister 32 and idler 34 so that the tow 20 as it passes aroundidler 34 is in a generally untwisted condition.

The twist is imparted to the tow in the following manner. The tow isthereaded through one of the slots 64 in the false twister insert 62 andextends linearlly through the bore of spindle 56. The tow 20, by meansof the centrifugal force exerted thereon by the rotating spindle 52, isurged toward the outer periphery of slot 64, as illustrated in FIGURE 4,so that the twister 32 imparts a twist to the tow 20. Slippage betweenthe tow 20 and the spindle slot 64 causes less twist than spindle speedwould indicate.

The tow 20, twisted in one direction, is heated in the furnace 30 andthe individual filaments are softened so that they are deformed andassume the twisted configuration. The binder bonding the filamentstogether is thermally decomposed in the furnace 30 and the filaments nolonger adhere to each other. As the tow 20 leaves the furnace 30 thefilaments quickly cool and harden while in the twisted deformedcondition. The tow 20 as it is untwisted between false twister 32 andidler 34 does not unravel or expand to any substantial extent. Thecrimped tow is wound on package 38 in a conventional manner, has adensity of about 30 to 40 pounds per cubic foot, and has the appearanceof a package of yarn.

The crimped tow is packaged and transported to distant lOcatiOns in thesame manner as yarn is presently transported. At the destination thecrimped tow is expanded with the apparatus illustrated in FIGURE 2. Allthat is required to expand the crimped tow 20 is a means to unwind thetow from the package, and a jet 74 which is provided with a suitablesource of air. The crimped tow 20 is threaded through apertures 84 and90 in jet 74 and disc 88 is adjusted. The air entering through conduit76 expands the crimped tow and the spacing of disc 88 regulates thediametrical dimension of the expanded tow.

It will be apparent that the process illustrated in FIG- URE 1 hasseveral variable operating conditions. Some of the variable operatingconditions are: the temperature of the tow in the furnace, the tightnessof the twist in the tow as it is heated and cooled, and the tension ofthe tow as it passes through the furnace. Due to the inherent difficultyin accurately measuring the above conditions, operating parameters maybe correlated to express the above conditions. For example, with afurnace of fixed longitudinal dimension the temperature of the furnaceand the linear velocity of the tow as it is pulled through the furnace(dwell time of the tow in the furnace) can be regulated to control thetemperature of the tow in the furnace. The speed of the twister and thelinear velocity of the tow as it is pulled through the twister can beregulated to control the tightness of the twist in the tow as it isheated and cooled, The tension of the tow can be controlled in aconventional manner and is readily measurable.

By a proper selection of the operationing conditions, it is possible topermanently deform the strands and filaments to preselected curvedconfigurations. For example, a yarn crimped under given operatingconditions will have strands and filaments that are permanently deformedinto a helical shape like a cork screw or a coil spring. By changing theoperating conditions slightly the crimped yarn will have strands andfilaments that are deformed in three dimensions and have the appearanceof a prolate cycloid in two dimensions with convoluted portions spacedat random intervals. The texture, resiliency, springiness, anddimensional stability of the fibrous product is dependent to some extenton the deformed shape of the strands and filaments.

The process for expanding the crimped tow also has several variableoperating conditions. It is believed that the air pressure and spacingof the disc in the air jet control the linear velocity of the towthrough the jet and the expansion of the tow. The air jet laterallyseparates a substantial number of the filaments in the strands andrandomly spaces and orients the filaments. The air also may breakcertain of the filaments at random intervals. The breaks in thefilaments are randomly spaced and do not interrupt the continuity of thetow.

One of the primary features of this invention is the deforming of thecontinuous filaments so that the filaments are mechanically engaged atrandom intervals so that the expanded tow is a continuous, multifilamentyarn. The expanded tow is dependent upon the mechanical engagement ofthe filaments to provide a unitary continuous product. The organicbinder that bonded the filaments to each other is thermally decomposedin the furnace and the filaments are dependent on their mechanicalengagement to hold them together. It appears that the filaments haverandom coils or convolutes that overlap and interlock to hold thefilaments together.

Example I About two hundred filaments of fiber glass having a diameterof aboutp00038 inch were formed into a single strand. An organic starchsize binder was applied to the filaments and the filaments were bondedto each other. Thirty of the above strands were grouped into a tow andthe tow was Subjected to a tension of about 50 g. and pulled through thefurnace and twister at a linear velocity of about feet per minute. Thetow was subjected to a temperature of about 1600 F. in a furnace havinga longitudinal dimension of five feet and the false twister was rotatedata speed of about 14,500 r.p.m. A crimped tow was formed and wound on apackage, The crimped tow had a density of about 35 pounds per cubicfoot.

The crimped tow was expanded by an air jet similiar to that illustratedin FIGURE 5. The jet was supplied with air at a pressure of about 80pounds per square inch and was adjusted so that the tow expanded to adiameter of about eight times its original diameter.

The expanded tow had a density of about 0.2 pound per cubic foot. Thefilaments in the expanded tow were deformed in three dimensions and in arelaxed statet random segments of the filaments had a prolate cycloidconfiguration in tWo dimensions. Under slight tension the expanded towelongated and the filaments assumed a helical configuration. A segmentof the expanded tow was subjecte dto a tension and elongated about oneand one-half times its original length and, when the tension wasrelieved, returned to its original longitudinal dimension. The expandedtow was stuffed into a flexible cloth-like container to a density ofbetween 4 and 6 pounds per cubic foot until the container had apredetermined thickness. The container was subjected to compressiveforce of 45 pounds per square foot for several days. The flexiblecontainer, after the compressive force was relieved, returned to itsoriginal thickness, illustrating the dimensional stability andresiliency of the expanded tow.

The thermal conductivity of the expanded tow Was measured at dilferentapproximate densities and different approximate mean temperatures andthe following measurements were obtained.

k B.t.u./in./hr./sq. ft./ F. at mean temp. of-

Density (lbs/cu. it.)

Example II Four hundred filaments of fiber glass having a diameter ofabout .00025 inch were formed into a single strand. An organic starchsize binder was applied to the filaments and the filaments were bondedto each other. Thirty of the above strands were grouped into a tow andthe tow was subjected to a tension of 50 g. and was pulled through afurnace having a linear velocity of about 150 feet per minute. The towwas subjected to a temperature of about 1500 F. in a furnace having alongitudinal dimension of feet and the false twister was rotated at aspeed of 14,500 r.p.m. A crimped tow was formed and wound on a package.The crimped tow had a density of 35 pounds per cubic foot.

The crimped tow was expanded by an air jet similar to that in FIGURE 5.The jet was supplied with air at a pressure of about 80 pounds persquare inch. The air jet was adjusted so that the tow was expanded to adiameter of about eight times its original diameter. The expanded towhad a density of about 0.2 pound per cublc foot. The filaments in theexpanded tow were deformed in three dimensions and had a generallyhelical configuration. The tow exhibited dimensional stability andresili ency.

Example III Thirty strands of fiber glass formed in the same manner asin Example I were subjected to substantially the same conditions as inExample I. Between the pulling roll 36 and the winding drum 42 thecrimped tow was threaded through the air jet and was subjected to airpressures of about 80 pounds per square inch. The disc in the air jetwas adjusted so that the crimped tow was expanded to a diameter aboutfive times its original diameter. The expanded crimped tow was thenwound on a package for use as a textured yarn in the weaving andknitting of fabrics. The expanded tow wound on the package had a densityof 7 pounds per cubic foot. The expanded crimped tow had desirableresiliency, elasticity and texture not previously available With yarnsprepared from fibrous glass filaments and appeared suitable for weavingas a fabric.

In summary, the fibrous product made by the process herein described isresilient and has dimensional stability. The fibrous product is free oforganic binders and is incombustible because it consists only of fiberglass filaments. The fibrous product has superior thermal conductivityand may be utilized as a thermal insulator at loW and high meantemperatures. The fibrous product retains the sound absorptionproperties of glass fibers and where porous protective surfaces areprovided can be utilized as a sound absorbing material. The fibrousproduct can also be utilized as yarn for knitting or Weaving fabricshaving improved properties of resiliency and texture.

We claim:

1. An article of manufacture comprising a high density, low bulk, woundpackage of permanently crimped fiber glass strand that resides in saidpackage under tension and in a substantially untwisted state.

2. The article of claim 1 wherein said package comprises a plurality ofsaid strand combined into a tow and the strands of said tow arecomprised of filaments oriented generally parallel to the axis of saidtow.

3. The article of claim 2 wherein said strands of said tow are comprisedof filaments having a permanently crimped shape extending in a pluralityof directions and said filaments are substantially free of binder.

4. The article of claim 3 wherein said filaments are intertwined andrelatively movable with respect to one another when said filaments aresubstantially free of ten- SlOIl.

5. The article of claim 3 wherein said strand on said package has adensity of 25 pounds per cubic foot to 50 pounds per cubic foot.

6. A high density, low bulk, wound package of fiber glass comprising acylindrical multifilament glass fibrous bundle wound on the package witha predominance of the individual filaments of said bundle having apermanent crimp about the central axis of said bundle.

7. The article of claim 6 wherein said multifilament glass fibrousbundle resides in said package under tension and in a substantiallyuntwisted state.

8. The article of claim 6 wherein said multifilament glass fibrousbundle is substantially free of binder.

9. The article of claim 7 wherein said filaments are intertwined andrelatively movable with respect to one another when said filaments aresubstantially free of tension.

10. A process for producing a multifilament fiber glass product whichcomprises collecting a plurality of longitudinally extending fiber glassfilaments into a bundle, heating said bundle to a temperature sufiicientto soften said filaments while twisting said filaments along the centralaxis of said bundle and cooling said softened filaments to impartpermanent crimp thereto.

11. The process according to claim 10 which further includes the stepsof untwisting said bundle and gathering said bundle into a package.

12. The process according to claim 10 which further includes the stepsof untwisting said bundle and moving said filaments relative to oneanother.

13. The process according to claim 11 wherein said bundle is gatheredinto a package by Winding.

14. The process according to claim 13 wherein said bundle is maintainedunder tension while winding said bundle into a package.

15. The process according to claim 14 wherein bundle contains binder andsaid bundle is heated temperature sufiicient to remove said binder.

16. A process for producing a multifilament fiber glass product whichcomprises collecting a plurality of longitudinally extending, sized,fiber glass filaments into a strand, crimping said strand, heating saidcrimped strand at a temperature suflicient to soften the filaments ofsaid strand and to remove size, cooling said softened filaments said toa

9 10 to impart parmanent crimp in a plurality of directions 2,691,85210/1954 Slayter et a1. and winding said strand under tension and in asubstan- 2,736,676 2/1956 Frickert. tially untwisted state into apackage. 2,797,529 7/1957 Mohr et a1 2872 XR 2,886,877 5/1959 Frickertet a1 5714O XR References Cited 5 3,060,674 10/1962 Slayter 57-140 XRUNITED STATES PATENTS DONALD E. WATKINS, Primary Examiner 2,975,5033/1961 Bacon et al. US. CL XK 3,080,736 3/1963 Mabru et 211. 3,118,2131/1964 Benson. 10 57--156;161154

